[#45534957] Updated line items index to include seller uuid parameter.
[#45535023] Added line item GET and PUT resources.
[#45535023] PSR-2 coding standard updates.
Merge pull request #31 from jamesiarmes/line-item-resources

[SPRINTFIX][#45534957 #45535023] Updated line item resources
[#50079207] Changed messagesGetBox() to work with changes in the public API.
[#50266257] Fixed ClientTest.php so that it will no longer have issues with capitalization.
Merge pull request #35 from jdarling91/FixClientTest

[#50266257] Fixed ClientTest.php so that it will no longer have issues with capitalization.
Merge pull request #33 from jdarling91/FixMessagesAfterAPIChange

[#50079207] Changed messagesGetBox() to work with changes in the public API.